EVALUATION AND STRENGTHENING OF EXISTING FLEXIBLE PAVEMENTS

Abstract

One of the major problem that has attracted tremendous interest of highway engineers/researchers for the past few decades is how to evaluate structural adequacy of pavements with a view to upgrading them to meet the demand of continuous increase in volume, frequency and speed of motor traffic, besides increased payloads on existing network of roads. Maintenance of roads is one of the major activities of every highway agency. Normally, the strengthening and maintenance operations are merely based on experience anA judgement. California Bearing Ratio is still used to work out the overlay thickness of t}1e road structure required to meet the demands of the increased traffic intensity. Though, this procedure has yielded satisfactory results in many cases, there are quite a few instances where it has not met with success. Besides being time consuming and_ laborious, CBR method is not ideally suited for several reasons, such as non-consideration of damaging effect of heavier loads, frequency in wheel load, spectrum and . also type of surfacing with its thickness requirements etc. In this study various overlay, design, methods such as rigid overlay, over rigid pavement, flexible overlay, over flexible pavement-, flexible overlay over rigid pavement and rigid overlay over flexible pavement have been discussed. in this review work.